Broccoli is one of the highlights of a vegetable garden, growing crisp and delicious during the chilly temperatures of early spring and fall.
Broccoli takes its names from the Italian words piccolo bracci, meaning “little arms”. The secret to growing broccoli is to encourage full, healthy flower heads but to harvest them before they mature and lose flavour.
Broccoli has several varieties such as sprouting broccoli, Romanesco broccoli, raab (or rapini), and purple cauliflower.
The crown portion of broccoli tastes great when cooked or steamed. The greens may also be eaten, and the stems can be used for soups or soup stock.
Timing: For a summer harvest, start broccoli indoors around the last frost date or later in spring. For a fall harvest, start indoors late spring and transplant in July. For overwintering varieties, start indoors late March to mid-April and harvest the following February to May.
Optimal temperature for germination is 10-30°C (50-85°F). Seeds will germinate in 7-10 days.
Sowing: Sow 3-4 seeds per pot, 5mm (1/4”) deep. Space transplants 45-60cm (18-24”) apart in rows 75-90cm (30-36”) apart. Thin to the strongest plant.
Growing: Broccoli is a moderate and heavy feeder. It does best in humus-rich soil amended with composted manure. Mix ¼ to ½ cup of complete fertilizer into soil under each plant.
When plants are 20-25cm (8-10”) tall, push soil around stems and up to the bottom of the first big leaf to encourage side shoots.
Ideal pH level of 6.0-6.8.
Harvesting: Cut the crown portion of the broccoli with 5 to 6 inches of stem - after it is fully developed, but before it begins to loosen and separate, and the individual flowers start to develop into bright yellow blooms. Removing the central head stimulates regrowth to develop for later pickings.
Side shoots will develop at leaf joints. Keeping this picked will continue the plant to produce fewer but larger side-shoots.
Protection: Row covers may be useful on small plantings to help protect plants from early damage. Put the row cover in place at planting and remove before temperatures get too hot in midsummer.
Pests and Disease: White maggots (larvae) attack all plants of the cabbage family. Damage causes wilting early on, death of plants later on.
To help reduce disease, do not plant broccoli or other Brassicas in the same location more than once every three or four years.
Companion Planting: All Brassicas benefit from chamomile, dill, mint, rosemary, and sage. Avoid planting near eggplants, peppers, potatoes, or tomatoes.
Broccoli tastes the best right after it is picked, although you can store it for up to a week after harvest.
Whether you steam it, bake it, sauté it, or serve it raw, a broccoli harvest will add a hearty nutritional boost to your meals.
Broccoli is high in vitamins A, C, and K, and rich in dietary fibre. It contains numerous anti-cancer compounds such as sulforaphane. Diets high in broccoli are thought to reduce the risk of aggressive colon cancer, increase innate immune response, and provide anti-viral and anti-bacterial agents.